I am sure there have been several topics of sort posted , but I am going to throw my two cents in. These are the MB dealerships/repair centers I have had dealings with.

Grand Blanc Motorcars: (Grand Blanc, MI): Toyota, MB, BMW: They have serviced my vehicles, but seem to have a little too much pride or is it arrogance?.......It's arrogance. I have gone there for different things and with the exception of 2 people, the service manager and parts manager-I just don't care for the attitude. I was admiring a 600SL and a saleman asked me if I was interested. I said I was just looking and it was too pricey for me anyway. He walked off in a huff and said "Well, it is a serious machine" Just the way he said it rubbed me the wrong way.

Williams Autoworld (Okemos, MI): Porsche, BMW, Mercedes Benz: Excellent in all aspects. Very nice people. I enjoy going there. Always greeted with a smile. No pressure. I went in on a saturday. Made it clear I was just a looker. I was invited in to look at the new carrera GT, offered coffee etc. I figure they knew I was'nt about to drop $450,000 on the car,but they were just excited to show it. Real good service. My wife stopped in with her M class to ask some questions and they were great.
Test drove a boxster there. They just seem to enjoy working there. Great place.

Motorwerks (Commerce Township, MI) : Repair Facility for ferrari, Lambo, BMW, Audi, MB: Awesome. NO SHOP LIKE IT ANYWHERE. Excellent prices, excellent work, very knowledgable. I recommend them in a heartbeat. There repair section of the business is like a dreamland with all the exotic cars they have back there. Also the cleanest repair room I have ever seen.